Mend.io Vulnerability Database

What is a CVE vulnerability ID? icon What is a WS vulnerability ID? icon What is an MSC vulnerability ID? icon
New vulnerability? Tell us about it!
icon

We found results for “”

CVE-2026-23951

Good to know:

icon

Date: January 21, 2026

SumatraPDF is a multi-format reader for Windows. All versions contain an off-by-one error in the validation code that only triggers with exactly 2 records, causing an integer underflow in the size calculation. This bug exists in PalmDbReader::GetRecord when opening a crafted Mobi file, resulting in an out-of-bounds heap read that crashes the app. There are no published fixes at the time of publication.

Severity Score

Related Resources (4)

https://github.com/sumatrapdfreader/sumatrapdf/security/advisories/GHSA-hj4w-c5x8-p2hv
https://github.com/sumatrapdfreader/sumatrapdf/blob/master/src/PalmDbReader.cpp
https://nvd.nist.gov/vuln/detail/CVE-2026-23951
https://www.mend.io/vulnerability-database/CVE-2026-23951

Severity Score

Weakness Type (CWE)

Integer Underflow (Wrap or Wraparound)

CWE-191

Out-of-bounds Read

CWE-125

CVSS v3.1

Base Score:
Attack Vector (AV): LOCAL
Attack Complexity (AC): LOW
Privileges Required (PR): NONE
User Interaction (UI): REQUIRED
Scope (S): UNCHANGED
Confidentiality (C): NONE
Integrity (I): NONE
Availability (A): HIGH

Do you need more information?

Contact Us